The present invention relates to a system, an apparatus and a program, and a method for performing printing via a network, and specifically, to a network data processing system, a network printing system, a data processing unit, a printer, a data processing program, a printing processing program, a network data processing method and a network printing method suitable for reducing network traffic volume and shortening the time elapsed before first print out.
Conventionally, in many offices of companies and the government, data processing units such as personal computers distributed with respect to each staff member (user) and printers such as color printers and laser printers are connected via a network such as a LAN and sharing is generally adopted, however, by this form, sometimes the traffic volume of the network increases and a long time is taken for the first print out between the time the printing request is made and the time the printing starts due to transfers of vast amounts of printing data and concentrations of printing requests.
Due to this, conventionally, for example, as shown in the Publication of Japanese Patent Application No. Hei-8-278862 and the Publication of Japanese Patent Application No. Hei-11-305974, a method is proposed for reducing network traffic volume and shortening the time elapsed before first print out by providing a storage part within the printer and storing printing data that has been printed in the printer in the storage part, and, when there is the same printing request later, the printing data stored in the storage part is used to perform printing processing.
In the conventional printing processing method, a remarkable effect can be obtained when printed materials have the same contents, however, with respect to a part of data of the printing data, for example, document data relating to formats and layouts of documents and image data and text data combined with the document data, when even a part of the data is different, the entire printing data including the different data part must be transferred, and reducing network traffic volume and shortening the time elapsed before first print out can be obtained only in a small part of the printing processing.
This is not limited to the case where a data processing unit performs printing with a printer via a network, but, for example, the same problem is assumed when plural data processing units share and edit a single piece of data.
Accordingly, the invention focuses attention on the unsolved problems of the conventional technology, and aims to provide a network data processing system, a network printing system, a data processing unit, a printer, a data processing program, a printing processing program, a network data processing method and a network printing method suitable for reducing network traffic volume and shortening the time elapsed before first print out.